With the rapid development of wireless networks such as Long Term Evolution (LTE) networks, 4G (the 4th Generation mobile communication technology) networks and 5G (the 5th Generation mobile communication technology) networks, great changes have taken place in people's lives, work, entertainment and communications. At the same time, people have higher requirements for wireless access terminals, such as wireless access routers, at homes, offices and other immobile sites.
Most of existing wireless access terminals have no built-in battery and are only powered by an adapter. Although some existing wireless access terminals have a built-in battery, such wireless access terminals can only work for a short time in an emergency such as power failure, due to small capacity of the built-in battery and large power consumption of the wireless access terminals. However, as people's lifestyle changes, outdoor activities become more and more frequent, and there is an increasing demand for outdoor use of wireless access terminals. Therefore, it is an urgent problem to be solved to provide an access terminal powered by an external mobile power supply.